The invention relates to assemblies for osteosynthesis of the spine, and in particular to the tools used while fixing such assemblies.
Numerous assemblies are known for the osteosynthesis of the spine, for example the assembly disclosed in document EP-0885 598. Such assemblies generally include anchor members in the form of screws or hooks that are connected to one another by one or more link elements in the form of rods or plates. The function of such assemblies is to rectify the shape of a deformed vertebral column or to enable osteosynthesis to take place in one or more fractured vertebrae. For this purpose, the anchor members are fixed rigidly to the vertebrae.
Each such member must be placed in a very precise position. For this purpose, tools are known that enable the member to be held temporarily so as to assemble it rigidly to the other parts in a desired position. Nevertheless, most such tools do not give satisfaction, either because they do not hold the member in satisfactory manner or because their size makes it necessary to release the member in order to be able to fix it to the other elements of the assembly. In particular, such tools do not give satisfaction when it is necessary to hold an anchor member whose head includes at least one branch.